@include b(dropdown) {
    // width: 100%;
    span {
        position: relative;
        width: 100%;
        cursor: pointer;
    }
    box-sizing: border-box;
    &:hover,
    &:active {
        color: $color-primary;
    }
    ul {
        position: absolute;
        top: $navbar-height;
        min-width: 150px;
        margin: 0;
        padding: 8px 0;
        left: -45%;
        top: $navbar-height;
        text-align: center;
        border: 1px solid $border-color;
        border-radius: 4px;
        z-index: 9;
        color: $font-color;
        background-color: #ffffff;
        box-shadow: 0 4px 8px 0 rgba(7, 17, 27, .1);
        li {
            list-style: none;
            height: 40px;
            line-height: 40px;
            font-size: 17px;
            font-weight: 500;
            background-color: #ffffff;
        }
        li:hover,
        li:active {
            background-color: rgba(62, 175, 124, .1);
            color: $color-primary;
        }
    }
}